x86/tdx: Rename TDX_ATTR_* to TDX_TD_ATTR_*

x86/tdx: Rename TDX_ATTR_* to TDX_TD_ATTR_*

The macros TDX_ATTR_* and DEF_TDX_ATTR_* are related to TD attributes,
which are TD-scope attributes. Naming them as TDX_ATTR_* can be somewhat
confusing and might mislead people into thinking they are TDX global
things.

Rename TDX_ATTR_* to TDX_TD_ATTR_* to explicitly clarify they are
TD-scope things.

Suggested-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Reviewed-by: Kiryl Shutsemau <kas@kernel.org>
Acked-by: Sean Christopherson <seanjc@google.com>
Link: https://patch.msgid.link/20260303030335.766779-4-xiaoyao.li@intel.com